Adjustable eccentric



Jan. 20, 1942. s. zoNls 2,270,816

ADJ US TABLE ECCENTRI 0 Original FiIed Dec. 7, 1937 2 Sheets-Sheet 1 Original Filed Dec. 7, 1937 2 Sheets-Sheet 2 Syn vendor Sydney Zonis Wifnefl: I

. Show,

Patented Jan. 20, 1942 ADJ US TABLE ECCENTRIC Sydney Zonis, Stratford, Conn., assignor to The Singer Manufacturing Company, Elizabeth, N. J., a corporation of New Jersey 4 Original application December 7, 1937, Serial No.

178,477. Divided and this application Septemher 2, 1939, Serial No. 293,173

8 Claims.

This invention relates to eccentrics and more particularlyto adjustable eccentrics, and has for its objective the provision of a plurality of eccentrics which are simultaneously adjustable by a single adjusting means.

Another object of this invention is to provide a plurality of eccentrics connected together so that when one eccentric is adjusted the other eccentric is adjusted an equal amount in a different direction.

With the above and other objects in view, as will hereinafter appear, the invention comprises the devices, combinations and arrangements of parts hereinafter set forth and illustrated in the accompanying drawings of a preferred embodiment of the invention, from which the several features of the invention and the advantages attained thereby will be readily understood by those skilled in the art.

Fig. 1 is a rear end elevation of a zigzag stitch sewing machine, the frame being shown in section to expose my improved adjustable eccentrics.

Figs. 2 and 3 are sectional views taken along the lines 2-2 and 33 of Fig. 1.

Fig. 4 is a vertical section taken substantially through the center of the eccentrics.

Fig. 5 is a disassembled perspective view of the two adjustable eccentrics and their connecting means.

In the embodiment of the invention selected for illustration my improved adjustable eccentrics are shown applied to a zigzag stitch sewing machine having a bed [0 carrying an overhanging bracket-arm H in which the needle-bar actuating shaft [2 is journaled. The shaft l2 may be driven from any suitable source of power and is connected to a second or auxiliary shaft 20 by means of the gears l4 and I5. For a more detailed description of the sewing machine reference may be had to my copending application Serial No. 178,477, filed December 7, 1937, now Patent No. 2,207,141, of which this application is a division.

The shaft 20 has fixed to it by the set screws 20 a disk 2| and secured by the pivot screw 22 which enters the aperture 22" in one face of the disk, is the flange 22 (Fig. 2) of an adjustable eccentric 23.

Diametrically opposite the pivot screw 22' is a shouldered screw 24 which extends through the arcuate slot 25 in the flange 22 and into the disk 2| to limit the movement of the eccentric 23 and to hold the eccentric against the disk.

To the other face of the disk 2! there is pivotally secured, by a pivot screw 26 which enters the aperture 26' in a flange 21, a second eccentric 28. A shouldered screw 29 passes through an arcuate slot 38 in the flange 21 and is screwed into the disk 2|. The flange 21 of the eccentric 28 is provided with a radial bore whichis tapped to receive the threads on a screw 32 formed with a reduced portion 33 which enters an aperture 34 in the shaft 20. The screw 33 may be adjusted and is held in its adjusted position by a jam screw 35. Diametrically opposite the adjusting screw 32 a plunger 36 is urged against the shaft 20 by a coiled spring 31 which reacts against a screw 38. On the flange 22 of the eccentric 23 there is provided an adjustable stop screw 3-9 which is adapted to engage the periphery of the shaft 20 and is held in its adjusted position by a jam screw 40. Also in the flange 22 and diametrically opposite the stop screw 39 is a plunger 4| which is spring urged against the shaft 20 by a spring 42. The two eccentrics are connected together by a link 44 having a centrally arranged offset. One end of the link is pivotally secured to the flange 22 of the eccentric 23 by a pivot pin.

45 which enters the hole 45 in the flange 22 and the other end is pivotally secured to the flange 21 by a pivot pin 46 which enters the hole 46' in the flange 21 (Fig. 5). From the foregoing it will be observed that the link 44 has one end on one side of the disk 2| and the other end on the opposite side and the link positively ties the two eccentrics. 23 and 28 together so that when the throw of one eccentric is varied the throw of the other eccentric will be varied an equal amount in a different direction.

Extending into the longitudinal bore in the hollow shaft 20 is an adjusting rod 48 (Fig. 4) having an enlarged portion 49 formed on one end with an inclined surface 50 which engages the reduced portion 33 of the adjustable screw 32 to thereby adjust the throw of the eccentrics. To prevent the adjusting rod being removed and also from turning relative to the shaft 20 a screw 5| enters the enlarged portion 49 of the rod and the head of the screw is guided by the walls of a slot 52 in the shaft 29. A threaded sleeve 53 embraces the reduced portion of the rod 48 and one of its ends engages the shoulder of the enlarged portion 49, the shoulder being held against the end of the sleeve by the nuts 56 on the other end of the rod 48. The sleeve 53 is provided with a knob 54 which is knurled and a flat spring 55 which engages the shaft 20 to increase friction. From the above it will be obvious that by turning the sleeve 53 the threaded portion, which coacts with the corresponding threads in the bore of the shaft 20, will cause the rod 48 to move in or out depending upon the direction that the sleeve is turned. This movement of the adjusting rod causes the inclined portion 50 of the rod, through the screw 32, to move, as a unit, the axes of the adjustable eccentrics 23 and 28 into or out of alignment with the axis of the shaft 20.

The eccentrics 60 and GI on the other side of the gear 15 and their adjusting mechanism are similar to the eccentrics 23 and 28 and their adjusting mechanism.

It is apparent that the construction described is susceptible of variations, and, therefore, the privilege is reserved of resorting to all such legitimate changes therein as may be embodied in the spirit and scope of the appended claims. 7

Having thus set forth the nature of the inven tion what I claim herein is:

1. In combination a driving shaft, a disk fixed to said shaft, a pair of driving eccentrics pivotally secured to the opposite sides of said disk, and a link having its ends pivotally connected to said eccentrics so that when one eccentric is moved the other eccentric will move an equal amount in a different direction and means for adjusting one of said eccentrics.

2. In combination a driving shaft, a disk fixed to said shaft, a pair of driving eccentrics pivotally secured to said disk on opposite sides thereof,

and a pivoted link connecting said eccentrics and means for adjusting one of said eccentrics.

3. In combination a driving shaft, a disk fixed to said shaft, an eccentric pivoted to one side of said disks, a second eccentric pivoted to the other side of said disk, means for adjusting said first mentioned eccentric and a link pivotally connecting said first mentioned eccentric with said second eccentric so that the adjustment imparted to the first mentioned eccentric is also imparted to the second mentioned eccentric.

4. A drive shaft, a pair of eccentrics each movably mounted thereon for variation of its eccentricity, adjusting means applied to one of said eccentrics to vary its eccentricity, and means other than the adjusting means for transmitting the adjusting motion of one eccentric to the other.

5. A drive shaft, a pair of eccentrics each pivotally carried by said drive shaft for variation of its eccentricity, an interconnecting link pivoted at its opposite ends to said eccentrics, and adjusting means applied to one of said eccentrics to vary its eccentricity.

6. A drive shaft, a pair of eccentrics each pivotally carried by said drive shaft for variation of its eccentricity, an interconnecting link pivoted at its opposite ends to said eccentrics, and means independent of said interconnecting link for adjusting one of said eccentrics.

7. In combination, a tubular driving shaft, a disk fixed to said shaft, an eccentric pivoted to one side of said disk, a second eccentric pivoted to the other side of said disk, 2. link having one of its ends pivoted to one of said eccentrics and its other end pivoted to the other eccentric, an adjusting rod located within the tubular driving shaft, and means carried by one of said eccentrics and cooperating with said rod for adjusting said eccentric an equal amount in difierent directions.

8. In combination, a rotary driving shaft, a disk fixed to said shaft, a pair of driving eccentrics pivotally secured to said disks on opposite sides thereof, means for adjusting one of said eccentrics, a link having one of its ends pivotally secured to one of said eccentrics and its other end pivoted to the other of said eccentrics so that both of said eccentrics are adjusted simultaneously and means carried by one of said eccentrics and cooperating with said shaft for adjusting the minimum throw of said eccentric.

SYDNEY ZONIS. 

